The present invention relates to a method of and to an apparatus for making stationery articles, such as steno pads, exercise books, calendars or like commodities wherein the sheets of stacks of overlapping sheets are held together by one or more pronged binding strips of the type known as wire-O (trademark). More particularly, the invention relates to improvements in a method and apparatus for making stationery articles by transporting a continuous strand of coherent binding strips having a generally C-shaped cross-sectional configuration to a severing station where the strand is subdivided into discrete strips and the thus obtained strips are thereupon transported sideways (i.e., transversely of their axes) toward a binding or inserting station where the prongs of the strips are introduced into the perforations of stacked paper sheets or the like.
U.S. Pat. No. 3,883,916 granted May 20, 1975 to Adams et al. discloses a machine for binding stacks of perforated sheets wherein a strand of coherent binding strips is fed axially to a severing station at which a tool severs successive strips, one at a time, and the thus obtained strips are moved sideways through a channel by a pusher bar, first onto a guide and thence into the range of carrier bar having magnetic attracting elements for the strip. An arm thereupon pivots the carrier bar about an axis which is parallel to the axis of the binding strip so that the strip enters a binding station and is closed by a pair of closing tools of the type disclosed in U.S. Pat. No. 3,451,051 granted June 24, 1969 to Liouville. The prongs of the strip penetrate into the perforations of the stationery article at the binding station so that the strip is converted into a generally tubular binder which allows the sheets or pages of the article to turn about the axis of the binder.
A drawback of the machine which is disclosed in the aforementioned patent to Adams et al. is that the number of stationery articles which can be turned out per unit of time is relatively low because the tool at the severing station is designed to separate from the continuous strand a single binding strip at a time, and that the number of strips cannot be increased at will since the strand is severed while its conveyor is at a standstill, i.e., the number of starts and stoppages of the conveyor cannot be increased to the extent which would permit the production of a large number of stationery articles per unit of time. The patented machine exhibits the additional drawback that it cannot be used for the making of stationery articles which employ so-called skip binders, namely, composite binders each of which consists of two or more aligned and spaced apart binding strips. Reference may be had to U.S. Pat. No. 3,555,587 granted Jan. 19, 1971 to Seaborn et al. FIG. 4 of this patent shows a stationery article wherein the sheets are held together by a skip binder consisting of three spaced-apart coaxial binding strips. Thus, in lieu of using a continuous binding strip which extends along the entire row of perforations in one marginal portion of a stack of sheets, a skip binder employs several shorter binding strips with attendant savings in the material of the binder. A feature of the machine which is disclosed by Seaborn et al. is that the binding strips are moved into engagement with the perforations of a stack of sheets while the stack moves along a predetermined path. As regards the manner of inserting the prongs of the binding strips into the perforations of the adjacent stacks of sheets, Seaborn et al. refer to U.S. Pat. No. 3,334,918 granted Aug. 8, 1967 to Pigna et al. The patent to Pigna et al. discloses an apparatus wherein the binding strips move with the respective stacks during insertion of prongs into the adjacent perforations, such insertion taking place by rotating the binding strips about their respective axes. Each of the above-discussed patents discloses the making of a single stationery articles at a time.